Postgres 15

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CREATE TABLE t
    ( user_id  int,  friend_id  int)
;
    
INSERT INTO t
    ( user_id ,  friend_id )
VALUES
    (134443, 5888),
    (232309, 8909),
    (232309, 185595),
    (232309, 172634),
    (232309, 118037),
    (80195, 46650),
    (80195, 80429),
    (80195, 216751),
    (80195, 224625),
    (175987, 175483),
    (175987, 243131),
    (175987, 141773),
    (175987, 226862),
    (247382, 68616),
    (247382, 183025),
    (101421, 91108),
    (101421, 159948),
    (101421, 12395),
    (101421, 55391),
    (201263, 104651),
    (201263, 175709),
    (201263, 243725),
    (201263, 141645),
    (241625, 266922),
    (241625, 184460),
    (241625, 103497),
    (241625, 16108),
    (4860, 175056),
    (4860, 103123),
    (4860, 184967)
;

CREATE TABLE



INSERT 0 30


select *
from   t


user_id
friend_id


134443
5888

232309
8909

232309
185595

232309
172634

232309
118037

80195
46650

80195
80429

80195
216751

80195
224625

175987
175483

175987
243131

175987
141773

175987
226862

247382
68616

247382
183025

101421
91108

101421
159948

101421
12395

101421
55391

201263
104651

201263
175709

201263
243725

201263
141645

241625
266922

241625
184460

241625
103497

241625
16108

4860
175056

4860
103123

4860
184967



SELECT 30


select   user_id
        ,count(*)
from     t
group by user_id
order by count(*) desc
fetch    first 1 rows with ties


user_id
count


80195
4

232309
4

175987
4

101421
4

241625
4

201263
4



SELECT 6

user_id	friend_id
134443	5888
232309	8909
232309	185595
232309	172634
232309	118037
80195	46650
80195	80429
80195	216751
80195	224625
175987	175483
175987	243131
175987	141773
175987	226862
247382	68616
247382	183025
101421	91108
101421	159948
101421	12395
101421	55391
201263	104651
201263	175709
201263	243725
201263	141645
241625	266922
241625	184460
241625	103497
241625	16108
4860	175056
4860	103123
4860	184967